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# Array Partition I

Given an array of**2n**integers, your task is to group these integers into**n**pairs of integer, say (a1, b1), (a2, b2), ..., (an, bn) which makes sum of min(ai, bi) for all i from 1 to n as large as possible.

**Example 1:**

```
Input: [1,4,3,2]

Output: 4
Explanation: n is 2, and the maximum sum of pairs is 4 = min(1, 2) + min(3, 4).
```

**Note:**

1. **n** is a positive integer, which is in the range of \[1, 10000].
2. All the integers in the array will be in the range of \[-10000, 10000].

## Solution

```
public class Solution {
    public int arrayPairSum(int[] nums) {
        Arrays.sort(nums);
        int sum = 0;
        for (int i = 0; i < nums.length; i += 2) {
            sum += nums[i];
        }
        return sum;
    }
}
```